In Bazzato U.S. Pat. No. 4,306,976, a peritoneal dialysis system is discussed having preattached plastic solution bags. One of the bags is initially filled with fresh peritoneal dialysis solution to be infused into a patient. The other bag is initially empty to receive spent dialysis solution.
This arrangement is desirable for numerous reasons. First, it represents a "closed" fluid delivery system. Second, it eliminates the need for the patient to make repeated connections between the administration set and solution bags. Third, the arrangement allows the patient to disconnect the administration set and attached bags during the dialysis period while the dialysis solution dwells within the patient's peritoneal cavity. All of these benefits are particularly important to a patient practicing continuous ambulatory peritoneal dialysis, or CAPD.
Solution administration systems having preattached plastic bags can pose manufacturing difficulties, particularly with regard to sterilization. In particular, when exposed to heat sterilization, the walls of the empty plastic solution container can stick or adhere together, effectively blocking off the interior of the bag. It can be difficult to later part these walls to drain spent dialysis solution into the bag.